Engineered high endurance in WO3-based resistive switching devices via a guided filament approach

Abstract

Resistive switching devices are promising candidates for the next generation of nonvolatile memory and neuromorphic computing applications. Despite the advantages in retention and on/off ratio, filamentary-based memristors still suffer from challenges, particularly endurance (flash being a benchmark system showing 10⁴ to 10⁶ cycles) and uniformity. Here, we use WO₃ as a complementary metal-oxide semiconductor–compatible switching oxide and demonstrate a proof-of-concept materials design approach to enhance endurance and device-to-device uniformity in WO₃-based memristive devices while preserving other performance metrics. These devices show stable resistive switching behavior with >10⁶ cycles, >10⁵-second retention, >10 on/off ratio, and good device-to-device uniformity, without using current compliance. All these metrics are achieved using a one-step pulsed laser deposition process to create self-assembled nanocomposite thin films that have regular guided filaments of ≈100-nanometer pitch, preformed between WO₃ grains and interspersed smaller Ce₂O₃ grains.